For different illnesses, the concentrations of various analytes in body fluids of the patient need to be regularly monitored. By way of example, the monitoring of the blood glucose concentration is an essential part of the daily routine for diabetics. In this case, the blood glucose concentration usually needs to be determined quickly and reliably several times during the day in order to be able to take appropriate medical measures if necessary.
Besides diagnostics, appropriate medication also plays a crucial part. By way of example, to compensate for fluctuations in the blood glucose concentration, a diabetic needs to take insulin medication matched to the measured blood glucose concentrations.
So as not to restrict the daily routine of patients, particularly diabetics, any more than is necessary, appropriate mobile devices are frequently used both for diagnostics and for medication which should be easy to transport and to handle, so that the measurement or the medication can be taken at work, while out and about or in one's free time, for example.
For the diagnostics, for example for determining a particular analyte in body fluids (for example in blood), particularly for determining blood glucose or lactate, it is necessary to obtain an adequate amount of this body fluid. To obtain a blood sample, for example, or another sample of a body fluid, a lancet is usually used to pierce the patient's skin on selected body parts, for example on the finger pad or the ear lobe. To make obtaining blood convenient, to control the depth of prick and to minimize the pain, various manufacturers supply lancing devices which insert a lancet in controlled and guided fashion into a skin part. Such a lancing device is described in EP 0 565 970 B1, for example. These lancing devices can also be mechanically connected in reversible fashion to a measuring device which is used to determine the analyte concentration, as described in EP 1 032 307 B1, for example. Despite this mechanical coupling, the lancing device and the measuring device continue to be units operating independently of one another, however, and together form a medical system.
The lancets are usually disposable products which, by way of example, comprise a highly sharpened metal pin and an integrally molded plastic holder which produce the connection to the lancing device. Other embodiments of lancets are also possible, however, for example lancets in the form of sharp edges or spines which are moved by the lancing device as appropriate.
On account of their generally comparatively simple design, lancets can easily be replicated or imitated, however. Frequently inadequate fits, inferior materials or lack of sterilization mean that replicated lancets or other consumables can cause considerable health risks and injuries during use, however. This applies particularly to invasive consumables, that is to say consumables which are set up to intervene in a body tissue of a patient (like lancets). A further drawback of such imitated consumables is that inadequate fits can sometimes damage the peripheral devices used. Furthermore, imitated consumables and replicas result in considerable financial losses for the effected companies and, in the case of malfunctions, a damage to reputation.
The lancets or other types of consumables may be arranged in a magazine, so that the user does not have to change the lancet prior to each use of a lancing device but rather replaces the magazine only at relatively long intervals of time, when all the lancets contained in said magazine have been used up. Such a system is described in EP 1 333 756 B1, for example. A product example of a lancing device with a lancet magazine is the lancing device “Accu-Chek Multiclix” from Roche Diagnostics GmbH. Lancet magazines can also be replicated with the aforementioned consequences for the affected companies. Lancets, lancet magazines and lancing devices are usually purely mechanical parts without electrical or analytical functions.
Similar problems to those described above for lancets also arise with other types of consumables. By way of example, it is also a fundamental possibility for consumables which have an analytical function (for example test elements or subcutaneous sensors), consumables for medication (for example cannulas, catheters or the like) or other types of consumables to be affected. Consumables in general are frequently also referred to as “disposables” in diagnostics.
From other areas of medicine, numerous different apparatuses and methods are known which are intended to ensure that medicaments or medical devices cannot be replicated. Today, for example, a large number of different technical solutions are used which include, by way of example, holograms or electronic identifiers, in particular radio frequency tags (RFID tags), which can be affixed to medicament packages, for example. RFID technology as an example of electronic identifiers comprises contactless identification by means of radio waves. The information in such an RFID tag, which is also called an RFID label and which contains an electronic chip, is usually transmitted wirelessly by radio at different frequencies to a reader which can then display and/or store the information. The use of RFID tags is advocated by the American health authority FDA to enhance the prevention of replication in the pharmaceutical industry, for example.
Electronic identifiers which can store a piece of electronically readable information are generally available in numerous designs. Besides designs which contain a silicon chip and an antenna (which is usually referred to as an RFID tag), for example, RFIDs are also known which are based on organic electronics (for example semi conductive or conductive polymers). In addition, inexpensive, printed designs of electronic identifiers are also known. These designs, also known as “chipless identifiers”, involve the piece of information being encrypted in an electrically conductive bar code, for example, and it then being able to be read contactlessly via numerous antennas in a reader. An example of such a design is disclosed in WO 2004/088037 A1.
The methods for enhancing the prevention of replication which are known from the prior art have some drawbacks, shortcomings and challenges of a technical nature in practice. Most methods require a complex reader and display device for checking the authenticity of the protected medical devices. This is usually not mobile and/or too expensive to be available to every user. In the case of the known methods, the user is therefore usually not able to recognize independently replicated medical devices, such as consumable materials.
Furthermore, a medical system is usually made up of a plurality of individual components which, even if some of said components can be integrated in a common housing or mechanically connected to one another, usually perform their functions independently of one another. An example is the cited lancing devices, which almost always have a purely mechanical functionality and which are not functionally correlated to a measuring device, which in turn is used for measuring an analyte concentration in a blood sample produced by means of the lancing device. To recognize replicated consumables, a user would therefore need to carry a separate reader which can read the identifiers, even in the case of the methods cited above for identifying these consumables. This is barely possible in many cases for reasons of space, however, and also represents increased cost outlay.
In addition, by way of example, purely mechanically operating peripheral devices, such as purely mechanical lancing devices, usually have no display option for displaying the information in the identifiers of the consumables. This means that the user cannot be provided with any information about said consumables, such as lancets. Even if a peripheral device, such as a lancing device, is mechanically coupled to a measuring device with a display option, as is the case with the commercially available products Accu-Chek Softclix Plus and Accu-Chek Compact Plus, for example, both devices are usually nevertheless functionally decoupled from one another, which means that the user usually has no way of reliably recognizing replicas, as previously, on account of a lack of explicit identification features of the consumables. Overall, it is therefore usually impossible for a user to himself recognize whether he is using a safe medical device or whether he is using a replicated lancet or a replicated lancet magazine or other types of unsuitable consumable materials.
Furthermore, current technical solutions for preventing replication have the drawback that they themselves can be replicated in many cases. This is the case with holograms, for example.
Other types of information transmission with other types of identifiers within units in medical engineering devices are also known and are presented in the examples below. The parts of the units are in this case generally functionally dependent on one another, which distinguishes the prior art described from the invention described below.
An example of information transmission between parts of a unit which are functionally dependent on one another is described in EP 1 574 855 A1, for example. These blood sugar measuring devices involve batch specific information being transmitted to the unit's measuring device from a test carrier optically or by means of wireless electronics (for example see DE 102 37 602 A1).
EP 1 043 037 A2 describes an injection apparatus with a pen which contains an expressible injection. The dosage when the injection is expressed is adjusted using a dosage adjustment apparatus. For visually impaired people, it is very difficult to adjust the dosage. An external display device is therefore provided which can be attached to the pen. Contacts and mating contacts are used to transmit a piece of information about the dosage to the display device and to display it on a large format display. In this case, it is also proposed that the pen be equipped with a coding, which can be recognized by the display device, in the form of elevations or depressions so that the display device always knows with which pen or pen type it is collaborating. The injection apparatus described in EP 1 043 037 A2 is tailored very specifically to one particular unit, however, and is therefore inflexible in the face of changing combinations of the individual components. Recognition of the pen requires a direct mechanical coupling to be made, and the system is inoperative if a pen which cannot be recognized by the display device is used.
EP 1 352 611 describes a measuring unit with a container for test elements, which container may be provided with an information chip in order to send information about the number and calibration data of test strips to a measuring device of the unit. In these systems, the RFID tag is used to forward necessary information to the measuring device, which information would otherwise have to be transferred to the measuring device using what is known as a ROM key or other information sources or else manually, for example, in order to allow the test strips to be evaluated. Accordingly, the RFID tag in the dispenser, as described in US 2006/0182656 and EP 1 352 611, is merely a variant for known methods and apparatuses in order to provide the measuring device with information which is necessary for the measurement, without which meaningful measurement or evaluation of the measurement would be impossible or possible only with difficulty. In this example of the prior art, the RFID technology is used to transmit information between the parts of a measuring unit.
US 2004/0138688 describes the identification of a lancet in which the identification is in the form of a bar code. However, this bar code does not have electronic information and therefore cannot be identified by a device which does not make direct optical contact with the consumable.
US 2007/0232879 A1 describes devices and methods for determining an analyte concentration. These involve the use of a mounting unit which is used for mounting a transdermal sensor. This mounting unit comprises, inter alia, an electronics unit which comprises, inter alia, an RFID identifier for identifying the sensor. Signals from said RFID identifier can be picked up by a receiver unit.
US 2002/0004403 A1 describes a unit which comprises a measuring head (BioInterface Head, BIH) with sensors for monitoring physiological parameters and which comprises a control module (Communication and Control Module, CCM) which actuates and reads the measuring head. In this case, a plurality of sensors may also be provided. Wireless data transmission can take place between BIH and CCM. In addition, identification management is also proposed which involves the interchange of information about the sensor type, for example.
WO 2006/065754 A2 describes a sensor dispenser which is set up to determine an analyte concentration in a body fluid. In this case, a cap of the instrument holds a cartridge with test strips, wherein calibration information from the cartridge can be transmitted to the instrument. In addition, the instrument comprises a lancet apparatus.
It is therefore an object of the present invention to provide a medical system and a method for monitoring a medical system which avoid the drawbacks of known medical systems and methods for monitoring such systems. In particular, the medical system and the method are intended to allow a user to independently, easily, reliably and quickly identify replicated consumables.